This work is a treatise on the construction and use of the weighing balance (qabān, also qapān). It brings together geometric, mechanical, and arithmetic knowledge needed to construct and utilize measuring devices for weighing heavy and irregularly-shaped objects. The author’s name is unknown, but excerpts from another work by an already-deceased Shaykh ‘Abd al-Majīd al-Shāmulī al-Maḥallī are quoted in the treatise. The last page of the manuscript contains a sheet of verses that describe the basics of using a weighing balance, in a form that is easy to remember ...